--- contrib/tools/cython/Cython/Utility/Embed.c	(index)
+++ contrib/tools/cython/Cython/Utility/Embed.c	(working tree)
@@ -234,7 +234,12 @@ int
         res = 0;
         setlocale(LC_ALL, "");
         for (i = 0; i < argc; i++) {
-            argv_copy2[i] = argv_copy[i] = __Pyx_char2wchar(argv[i]);
+            argv_copy2[i] = argv_copy[i] =
+#if PY_VERSION_HEX < 0x03050000
+                __Pyx_char2wchar(argv[i]);
+#else
+                Py_DecodeLocale(argv[i], NULL);
+#endif
             if (!argv_copy[i]) res = 1;  /* failure, but continue to simplify cleanup */
         }
         setlocale(LC_ALL, oldloc);
         free(oldloc);